Support

ABSTRACT

A skid is provided for supporting a drawn implement, such as a mower. The skid includes a convex ground-engaging disc mounted to a support for rotation about a first axis. The support is adapted to be attached to the implement for rotation about a second axis. The first and second axes are co-planar and form an acute angle.

TECHNICAL FIELD OF THE INVENTION

This invention relates to the field of implements which are eitherpushed by a vehicle or drawn.

BACKGROUND ART

A variety of implements which may be towed by a vehicle is known in theart. For example, the known rotary mower is attached to a draft vehicleby a three-point hitch, and a wheel is attached to a bar which projectsrearwardly from the mower. The wheel may be of the castering type.

Other implements are known which may be pushed by a vehicle, such as aearth-moving blade. An earth-moving blade, such as that shown in theU.S. Pat. No. 1,961,011, may have pads on the bottom of the blade forsupporting the weight of the blade. These pads may be circular and aretypically mounted so that they do not rotate. Hence, they merely act asground contact pads so that the edge of the blade does not dig into theground.

It is also known to employ pads to support the blade of a mower. U.S.Pat. No. 3,415,043 shows such an apparatus. The mowing blade is mountedon a rotating shaft for vertical movement within fixed limits. Attachedto the bottom of the shaft is a pad which rides along the ground andmaintains the height of the cutting blade at a constant distance abovethe terrain. Similarly, U.S. Pat. No. 4,233,805 shows a mower havingpads directly below the mowing blades to support the weight of themower.

It is also known to use pads for supporting other implements. U.S. Pat.No. 3,960,219 shows a cultivating implement having pad-like supports.These supports are rotatable and have projections on their bottoms toinduce rotation to aid in the cultivation.

STATEMENT OF THE INVENTION

The typical mower having a castering wheel for supporting the mowerssuffers from several disadvantages. When used on rough terrain, thewheel is hard to control and is easily damaged. The standard rear wheelof a mower tends to follow ruts in the field being mowed thus placingundue strain on the mower and resulting in an uneven, or jerky, motionof the tractor.

The invention is a skid for replacing the rear wheel, particularly acastering wheel, in a drawn implement. The skid is convex and is mountedto a bracket for rotation about a first axis. The bracket is, in turn,mounted to the implement for rotation about a second axis. The first andsecond axes are co-planar, but are not parallel. This arrangement allowsthe combination of the bracket and the skid to caster, and also allowsthe skid to rotate relative to the bracket. These two degrees of freedomresult in an easily controlled implement, and the skid overcomes thenoted disadvantages of a wheel.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective of the skid of the invention attached to a knownmower.

FIG. 2 is an elevation of the apparatus of the invention.

FIG. 3 is a cross-section of the apparatus of the invention along line3--3 of FIG. 2.

DETAILED DESCRIPTION OF THE INVENTION

A prior art mower 2 shown in FIG. 1 has an arm 4 extending rearwardly ofthe mower. A support 6 comprises two plates 8 and 10 and bolts 12 and 14located, respectively, balanced above the arm 4. The support 6, thus,grasps the arm 4, and the arm 4 supports the rear portion of the mower2. The mower may be of a known type which is attached to a tractor by aknown three-point hitch.

The end of arm 4 includes a cylindrical mounting element 16 which isknown in the art for use in receiving a castering rear wheel. FIG. 1shows the arm 4 supported by the inventive skid which includes a bracket18 and a convex disc 20. The bracket 18 includes side plates 22, topplate 24, and bottom plate 26. A shaft 28, seen more clearly in FIGS. 2and 3, extends from the top plate 24 and is received by the cylindricalmounting element 16. The bracket 18 is thus mounted for rotation aboutthe axis of the cylindrical mounting element. A bolt 30 may pass througha hole in the upper end of the shaft 28 to secure the shaft in themounting element. A grease connection 32 allows the shaft 28 to belubricated.

Convex disc 20 comprises two convex elements 34 and 36.

The upper convex element 34 is secured to the bracket 18 for rotationwith respect to the bracket.

As seen in FIGS. 2 and 3, the convex discs 34 and 36 are securedtogether at mating circular edges. Second shaft 38 is attached to abearing-receiving element 40 which is attached to a mounting plate 42.The mounting plate 42 is attached to the outside surface of convexelement 34, for example by welding. Shaft 38 is received in a housing 44and is supported for rotation with respect to the housing by bearings 46and 48. A nut 50 secures the shaft to the housing 44. The bearings 46and 48 may be any suitable kind, and in the preferred embodiment thesebearings are Timkin roller bearings. Housing 44 has a flange 54 whichreceives bolts 52 for securing the housing to the lower plate 26. Thehousing 44 may be attached to the lower plate 26 by other known means,for example as by welding. A dust cap 56 covers the end of housing 44and prevents dust from contaminating the bearings 46 and 48.

As seen in FIG. 2, the axis of rotation of shaft 28 is co-planar withthe axis of rotation of the shaft 38. As seen in FIG. 3, these axes arenot parallel.

It may also be seen in FIG. 3 that the convex discs 34 and 36 aregenerally spherical, and their centers of curvature lie on the axis ofrotation of shaft 38.

When the skid of the invention is mounted on a mower as shown in FIG. 1,the convex disc 36 engages the ground and supports the rear of the mower2. As the tractor drawing the mower changes direction, the skid mayrotate about either shaft 28 or shaft 38. Typically, the apparatusrotates about shaft 28 in a generally castering fashion, while the disc20 rotates about shaft 38 as it slides across the field. This rotationis not continuous in a single direction, but is instead in alternatedirections.

When mounted on a mower, the shaft 28 has a slightly forwardinclination. The shaft 38 is then tilted rearwardly to prevent the frontportion of convex disc 20 from digging into the ground and to allow therear portion of the disc to engage the ground. The angle of inclinationof the disc is preferably about 15 degrees with respect to the ground.Of course, other inclinations are useful, as will be appreciated bythose of skill in the art.

It is claimed that:
 1. A support for an implement comprising a convexdisc, bracket means comprising mounting means for mounting said convexdisc to said bracket means for rotation with respect to said bracketmeans about a first axis transverse to said disc and supporting meansfor attaching said bracket means to said implement, wherein saidsupporting means allows said bracket means to rotate with respect tosaid implement about a second axis.
 2. The support of claim 1 whereinsaid convex disc is spherical, and the center thereof lies on said firstaxis.
 3. The support of claim 1 or 2 wherein said first and second axesare co-planar, and are non-parallel.
 4. The support of claim 3 whereinsaid first axis is vertical when said implement is in an operatingposition, and said second axis is tilted toward a direction in whichsaid implement moves.
 5. The support of claim 4 wherein said convex dischas a first convex ground-engaging portion and a second convex portionattached to said mounting means, the centers of curvature of said firstand second convex portions being on said first axis.
 6. The support ofclaim 5 wherein said means for supporting is adapted to be attached toan arm which extends rearwardly from said implement.
 7. In a drawnimplement, of the type which is connected to a tractor by a three-pointhitch, and having a castering means for mounting a castering rear wheel,the improvement comprising a convex disc for engaging the ground,bracket means mounting said convex disc for rotation about a first axistransverse to said disc and for cooperating with said castering meansfor allowing said bracket means to rotate about a second axis.
 8. Theimplement of claim 7 wherein said convex disc is spherical and thecenter of curvature of said disc lies on said first axis.
 9. Theimplement of claim 8 wherein said first and second axes are co-planarand non-parallel.
 10. The implement of claim 9 wherein said second axisis vertical when said implement is in an operational position, and saidfirst axis is tilted toward said hitch.